Various arrangements of keyboards to permit variable positioning of a user's hands have previously been suggested. These include the keyboards disclosed in the international PCT application of Goldstein (international publication number WO 92/00851) and U.S. Pat. Nos. 4,597,681 to Hodges, 5,067,834 to Szmanda et al, 5,122,786 to Rader, and 5,228,791 to Fort, for example.
The aforesaid Goldstein application discloses a keyboard having two segments or sections of different sizes connected to each other at their upper ends by a hinge, which may be a ball and socket joint. The aforesaid Goldstein application lacks any suggestion of holding the two segments in their adjusted positions when connected to each other. The aforesaid Goldstein application also has no teaching of holding the two segments, when detached from each other, at different positions with respect to a support surface such as a desk top, for example. The aforesaid Goldstein application has its space bar on its right segment terminate at the location of the character N key. A touch typist normally uses the thumb of the right hand to actuate the space bar, and the locations of the fingers of the right hand result in the thumb engaging the space bar to the left of the character N key. Thus, the right segment of the aforesaid Goldstein application would require a touch typist to change the way the space bar is struck or have difficulty in striking it.
The aforesaid Hodges patent requires a pair of base plates to be hingedly attached to each other with each of the base plates having a keyboard section pivotally connected thereto. This is a complicated arrangement that significantly increases the cost. The two sections also are not separable from each other so that the amount of relative movement between the two sections is significantly limited. Additionally, the right keyboard section does not have the space bar extending beyond the character N key in the same manner as the aforesaid Goldstein application.
The aforesaid Szmanda et al patent has a keyboard formed of two segments connected at their upper ends by a ball and socket connector and each of its segments supported on a telescoping support, which is universally connected by a ball and socket joint to a sliding attachment unit. This arrangement is both complicated and expensive. Furthermore, the space bar appears to terminate beneath the character N key. Additionally, the keys appear to have a rectangular configuration rather than having a standard keyboard arrangement in which keys in adjacent rows do not vertically align but are slightly shifted or staggered. This presents the problem to a touch typist of not being able to reach the keys properly because of the shifting of their positions from the standard keyboard arrangement.
The aforesaid Rader patent discloses two keypads with one being substantially larger than the other. The two keypads, which are mounted on separate support posts, also may be hingedly connected to each other. The aforesaid Rader patent does not have a standard keyboard arrangement or a standard space bar.
The Fort patent has a keyboard formed of two segments with each segment being separately mounted on a support through a ball and socket joint. The right segment of the keyboard has a space bar positioned to extend beyond the character N key. However, a separate support for the two joints is required to enable the two segments to be disposed adjacent each other. This is a relatively expensive keyboard.